Researchers Create 3-Dimensional Chips

Spy der Mann writes "Professor James Lu and other researchers of the Rensselaer Polytechnic Institute, managed to create three-dimensional chips (coral cache) to optimize the design of future processors and prevent overheating. "Make the interconnect wire shorter, and you cut the delay time," says Lu. "A simple way to make them shorter is to stack the transistors.""

Comments

How does that prevent overheating?

[Kjella]

Essentially, they say this packs it denser. And a cube vs a flat processor = less surface/transistor. I see only factors which makes this *harder* to cool. Maybe someone can explain...

Kjella

Re:shorter wires = less resistance

[jumpingfred]

Most of the heat is disapated accross the transisors. Shorter wires may reduce the capacitance which would lower the amount of charge moving which would lower power.

Re:shorter wires = less resistance

[geekee]

"There is, sort of. If the wires are shorter, they have less resistance end-to-end assuming they have the same thickness, are made from the same material, etc etc. Less resistance means less heat (and maybe core voltage could be lowered slightly too, since there would be less of a voltage drop). However, I honestly don't know how much heat comes from the actual junctions versus circuit pathways."

I don't think people are worried about the heat dissipated in the actual wire. High resistance wires require you to use additional buffers to generate signals with acceptable rise/fall times due to rc charging effects. This costs more power.